Spaceframe structures have long been known and applied to special architectural and engineering problems. Spaceframes are hyperstatic support structures. They have evolved out of the quest to better utilize the tensile properties of materials in order to achieve higher performance load-carrying capacities in frame structures. These improved structural characteristics are achieved through the high repetition of a basic, triangulated, self-bracing geometry expressed in a three dimensional truss-like framework.
The main focus of improved spaceframe design is the design of the connecting means; usually a nodal arrangement which joins together the ends of elongated frame members and which provides for the transfer and distribution of loads in the realized structure.
Contributing to the cost and limited application of spaceframes are two basic types of problems exhibited by previous spaceframe connectors: (A) the connectors are comprised of many parts, first to be manufactured and later be simultaneously handled in an assembly procedure; and (B) the connector requires a sequence of many assembly steps during field construction. Typically, the sequence cannot be optimized due to inherent charactertistics of the connector design itself. These problems are further compounded by the highly repetitive geometry which demands close manufacturing tolerances of all parts and which contributes to the time consuming process of frame alignment and connector adjustments during assembly.
Another major limitation of previous approaches to spaceframe design is the lack of variability of possible shapes of spaceframe structures. In order for common building practice to more fully benefit from spaceframe technology, a connecting means should be capable of producing a range of space-enclosing shapes such as curved vaults and upright cylinders. Previous spaceframe connectors require geometric or structural modifications in order to be used for curved spaceframe applications. In addition, these connectors require separate manufacture for each change of angular curvature and each change in structural specification.